title: Crystal growth of new hexahydroxometallates using a hydroflux.
abstract: A series of seven compounds, Sr2Mn(OH)6, Ba2Mn(OH)6, Sr2Co(OH)6, Ba2Co(OH)6, Sr2Ni(OH)6, Ba2Ni(OH)6, and Ba2Cu(OH)6, were synthesized using a low-melting hydroflux, a hybrid approach between aqueous hydrothermal and molten hydroxide flux techniques. Crystals of the hexahydroxometallates were obtained by dissolving appropriate amounts of alkaline-earth nitrates or hydroxides and transition-metal oxides, acetates, or chlorides in the hydroflux and reacting at 180-230 °C. The isostructural compounds all crystallize in the monoclinic space group P2(1/n). The monoclinic structure consists of isolated transition-metal octahedra within a three-dimensional framework of corner- and edge-shared eight-coordinate, alkaline-earth polyhedra. Magnetic susceptibility data show that all compounds are simple paramagnets. Thermogravimetric analysis indicates that these hydroxides lose water between 215 and 350 °C and transform into oxide products, the identity of which depends on the metal cations present in the parent hexahydroxometallates.
authors.affiliation: Department of Chemistry and Biochemistry, University of South Carolina , Columbia, South Carolina 29208, United States.
authors.forename: W Michael
authors.initials: WM
authors.lastname: Chance
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Bugaris
authors.forename: Athena S
authors.initials: AS
authors.lastname: Sefat
authors.forename: Hans-Conrad
authors.initials: HC
authors.lastname: zur Loye